Key bolt



April 28, 1931. BELL 1,803,090

KEY BOLT Filed Aug. 1, 1927 4 HT A Huh-- 9 Patented Apr; 28, 1931 UNITEDiseaae ATENT. QFFECEY;

FRANK B. BELL, or PITTSBURGH, PENNSYLVANIA KEY BoLr Application fildAugust 1, 1927. serial 1110101724.

the provision of a novel key-bolt construction comprising a slottedbolt, a key arrangeable through said slotted bolt, and means forautomatically deforming the key to lock it in place as it is arranged inengaged position.

A further object of the invention is the provision of a key-boltconstruction comprising a bolt having a slot therein and a key adaptedfor engagement through the slot, and a gib key also arrangeable in theslot and adapted to deform the key as it is arranged in engaged positionin the slot to provide a means for locking the same in engaged position.

Still another important object of the invention is the provision of akey bolt construction having a self-locking key.

Numerous other objects of the invention will be apparent as it is betterunderstood from the following description, which, taken in connectionwith the accompanying drawthereof.

Referring to the drawing: Fig. 1 is a perspective view of a key-boltconstruction embodying my invention:

Fig. 2 is a cross-section taken substantially along line 22 of Fig. 1;

Fig. 3-is an enlarged perspective view of a gib key providing theautomatic feature of the:it key-bolt construction of my invention; an

Fig. 4 is a cross-section of parts taken substantially along line H ofFig. 1 and illustrating the locking operation of the gib key. Tolllustrate my invention I have shown on the drawings a bolt having ashank 11 and a head 12. A rectangular diametral slot 13 having upper and7 lower parallel edges 14; is formed through the shank of the bolt. Akey 15, formed of a strip of iron or other convenient key material andhaving a ings, discloses a preferred embodiment thickness sufficient toallow engagement of the key between opposite lateral sides of the slot-'13, is provided for engagement-in the inner portion'of' the slot, and agib key 16,

of substantially the same thickness, is adapted for engagement throughthe outer portion of the slot. i

The gib key comprises a rectangular body 17 the thicknessof which issuch'asto allow its easy insertion through the slot'13, the

key having a sliding fit between the lateral;

sides of the slot. Atone end of the keyfa shoulder 18--is formed and"protrudes from an edge 19"ofjthe body. At the opposite end of thewkey asecond shoulde'r'21 is formed which protrudes from the opposite j edge22. The shoulder 21, at its lower edge 23, lies in the plane of thefbody17, but the upper portions of theshoulder Qlarebfiiset from the planealong lines of bend 24', the plane of the shoulder portions being 'dis-.7. posed at an angle with the plane of the body '17, and the upper edge25 of theshoulder be ing displaced from the'plane of the body a distanceequal tothe thicknessof thebody.

The key 15 comprises a strip of suitable? material and is substantiallyrectangular in cross section'having parallel upper and lower edges 31.and 32. A slot or kerf 33 is formed inthe body of'thekey parallel'withthe sides 31 and 32 and extends from one 'end & ofthe key to adjacentthe other, terminating at an enlargement 34 and dividing the key intotwo prong portions 35 and 36,the latter having a width equal tothe'width of the shoulder portion 18 of the-gib key. The 5 key15 and thegib key'16 are arranged to be 'adjac'entl y mounted in the slot, thesumfof the width of. both keys being substantially equaltothe.-total--width of the slot 13 between upper andlower sides. I 5,9 Thegib key is first arranged in the outer portion of the slot 13, the edge19 having engagement with the outer side 14 of the slot, and theshoulder 18 engaging the side of the bolt immediately adjacent theslot.a The main strip 17 of the gib key extends through the slot and theshoulder 21 is arranged adjacent the opposite side of the bolt, theoffset upper edge of the key engaging the surface of the bolt adjacentthe lateral j edge of the slot opening. The gib key is assembled in theslot by inserting the end having the shoulder 18 through the slot fromone side of the bolt and arranging the key in position in the outerportion of the slot.

' The key 15 is then inserted into the inner slot portion from theopposite side of the bolt, that is to say, the side of the bolt fromwhich the head of the gib key protrudes. The key 15 is assembled throughthe slot 13, the edge 31 of the key having sliding engagement with theinner slot wall 14 and the other edge 32 of the key sliding upon theadjacent edge 22 of the gib key. As the key is driven through the slot,the end 37 of the prong portion of the key engages the sloping shoulder21 of the gib key and is deformed thereby gradually assuming the finalposition illustrated in Fig. 2 of the drawings, as the key is forcedinto engaged position in the bolt. The key 14 is automatically deformedas it is forced into position in the bolt and being so'positioned cannotbe withdrawn from the slot without laboriously unbending the curled-upportion 37.

The arrangement thus provides a self-locking'key-bolt construction, theparts of which are simple and inexpensive and yet sufliciently rugged togive adequate key-bolt service. 7 v

It is thought that the invention and many of its attendant advantageswill be under stood from the foregoing description, and it will beapparent that many changes may be made in the form, construction andarrangement of the parts Without departing from the spirit andscope ofthe invention or sacrificing all of its 'material advantages, the

' form hereinbefore described being merely a preferred embodimentthereof.

Iclaim: v 7

The combination of a bolt having a slot formed therethrough, a gib keymounted in said slot and having shoulders engaging the face of the'boltshank onopposite sides, and a locking key arranged through the remainderof the slot and having a part deformed I by a said shoulder of the gibkey, said deformation causing the locking key to engage the face of thebolt shank to lock against retraction-in one direction, the othershoulder of the gib key preventing dislodgment 1 thereof. the oppositedirection.

FRANK B. BELL.

